A cluster analysis interpretation of Middle Ordovician biofacies, southern Mackenzie Mountains

• Published in: Canadian Journal of Earth Sciences
• Main Author: Hayes, Brad J. R.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1980
• Subjects: General Earth and Planetary Sciences; Mackenzie mountains
• Online Access: http://dx.doi.org/10.1139/e80-145; http://www.nrcresearchpress.com/doi/pdf/10.1139/e80-145

Collections of fossil trilobites, ostracods, bryozoans, and conodonts from Chazyan and Blackriveran strata of the southern Mackenzie Mountains are analyzed in an attempt to define biofacies, in terms of areal extent and faunal composition. Q-mode and R-mode cluster analyses, using Jaccard's coefficient and the unweighted pair-group method of clustering, are employed to delineate five biofacies. The interpretation of sedimentological features and composition of faunal assemblages shows that one nearshore biofacies, three progressively deeper shelf biofacies, and one continental slope biofacies are represented. A plot of biofacies succession through time in each measured section provides added support for the biofacies interpretations.